Propeller.



No. 853,999. I PATENTED MAY 21, 1907. W. SCHMID. PRORELLER.

APPLIOATION FILED NOV. 20, 1905.

2 SHEETS-SHEET 1.

I 57 $4 WWI-Q 11 q I 1 No. 853,999. PATENTED MAY 21, 1907.

W. SGHMID.

. PROPELLER.

APPLICATION FILED NOV. 20, 1905. T 2 SHEETS-SHEET z.

I- E STATES. PATENT j I orscHArFHAUsEN, SWITZERLAND.

PROPELLER.

no. eaa,999. Specification of mm- Patent. latonted my 21, 1907.Application ma as... so, 1900. Burial I. 288,148.

To all whom y of the propeller-blades. The bottom of each Be. it knownthat I, WILIIELM Scmrm, a citizen of the Re ublic of Switzerland, andaresident of Scha ausen, Switzerland, have invented a certain new anduseful Improvement in Propellers, of which the following is a sc1fication.

he present invention relates to improved means for reversingpropeller-blades y fluid under pressure, the fluid being permitted toact on the specially formed roots of the blades, without anyintermediate lines EF and F- longitudinal section on line the hub ofFig.5.

members bein interposed.

Two e'mbo iments of the invention are illustrated in the accompanyingdrawings in which Figure 1 represents a longitudinal section through thetwo ends of a propeller shaft. Figs. 1 and 1? show the form of recessesfor, and the shape of the roots of ropellerblades. Fig. 2 is alongitudinal section along the hne A--B of Fig. 1' and Fi 3 a transversesection on the line C.D of Fig. 1. Fig. 4 is a plan of the propellershowing the two-part nut and the angular displacement.

of propeller-blades. Fig. 5 shows a modification. Fig. 6 a lo 'tudinalsection along of 5. Fi 7 a B of ig. 5. Fig. 8 a cross section throughthe center of Referring to the drawings, the pro eller- I shaft 1 ishollow throughout its entire ength and in its bore is inserted a tube 2closed at its rear extremity 3; its external diameterexact y in thelower or deeper portion of its recess, forms a collar and shoulder(Figs. 1

"the ivots 6 are also and 1') by which the blade is'secured down in its,seat by means of the two part nut 7 (Figs. 1 and 4) lodged in theenlarged outer portion of the recess. The bottom faces of ro ,ided withrecesses 10 s aped as shown in Fig. 1 and Fig. 2; the angle of thesector-shaped portion corresponds to the required angular displacementpivot of each blade being made to fithub-recess is provided with acentral stud or pm 8 and a partition plate 9 dividing thesector 10 intwo separate chambers (Figs. 2 and '7) into one or other of which thepressure medium is admitted to effect the reversal of thepropeller-blades in the desired sense, one or other face of thepartition-plate 9 serving as'an abutment to the pressure. Two borngf; 11and 12 (Figs. 1 and 2) open upon the tu e 2, boring 1 1 communicatingwith the interior of tube 2 and boring 12 with the bore of the shaft 1.In order to allow the face access of the fluid, when thepropeller-blades occupy their two extreme or working positions, thelimiting faces of the sector are sli htly concave.

he forward end of the shaft 1 terminates in the thrust bearing 13, Fig.1 which is fixed in the turbine casing 14. Upon this latter is mountedthe pump 15 by means of which the pressure is imparted to the fluid(preferably oil). The pump may be driven by steam from the shipsboilers. At the front of the turbine-casing 14, and thrust bearing 13 ismounted a cock-casin 16 provided with a pair of three-way coc 17 and 18.These two cocks are coupled and are actuated by a common operating lever19. Instead of the three-way cocks, two pairs of valves may preferablybe used. The forward extremity of tube 2 enters the central chamber 20in the cook or valve casing, whereas the fore-end of the shaft (on towhich the thrust-bearing 13 is attached by meansof the nut 21) isstepped at its extremity and packed in a stuffing box 22 in which itrevolves with the shaft. The cocks 17 and 18 communicate with pump 15through the two connecting pipes 15 and 15. From cock 17 one passagebored in the cock-casing leads to the central chamber 20 while thesecond passage opens into the annular exit-chamber 24; From cook 18 onepassage 27 communicates with the annular shaft-conduit and the otherpassage also 0 ens into the annular exit-chamber 24.

his latter communicates through the con- IIC 2 and consequently throughthe hub-boring 11 on to one side of the partition plate 9, the othercock 18 establishes communication (for the back-flow) between theopposite side of plate 9, the hub-boring 12, the annular shaft conduit,the-passage 127 with the annular exitchamber 24 and finally with thereservoir 26. Nhen, on the other hand, the operating lever 19 takes theposition ill, the functions of the two cocks are exchanged, viz: theirinlets and outlets for the conduits are inverted.

The simultaneous admission of high-pres sure fluid to the one side ofthe three partition plates 9 and of the three recesses 10 and pivots 6,and the simultaneous discharge of the low presure fluid from theopposite sides of the three partition plates, produces the simultaneousand equi-directed reversal hi all the blades in the desired sense. Inmidway position II of the lever 19 all the supply conduits from thepumps, are obturated by the cocks.

If the blades have such a form that, while exerting their propellingeffect, the thrust center of the re-acting Water assumes such a positionin relation to their pivoted axis as will tend to adjust the blades inthe same sense as the pressure fluid does, then the blades after theirreversal by the action of the pressure-fluid, will be automaticallylocked in their new working positions by the thrust of the re-actingwater itself, assisted; by the friction of the jamming action in thepivots. The further admission of pressure fluid may then be discontinuedby shifting the operating lever into its mid position I1.

driven propellers, when going ahead, is gen- The arrangement may,however, also be 'made in such a manner, that the locking of the bladesin their working positions is effected solely by the continual admissionof the pressure fluid. By a similar arrangement the blades may be lockedin any desired position, such for instance, as to offer the leastresistance to the motion of the ship, while the particular propeller andits motor 1s at rest.

The operation of the apparatus is as follows: When the ships motion isto be reversed, say frornmovement ahead to movement astern, theoperating lever 19 is brought;

into position III and the pump is started,

either automatically or by hand, whereby the fluid pressure is admittedto the pivots:

' of the blades and their reversal effected in the manner described. Ifthe blades are-selflockmg, the action of the pump may, after thereversal is completed, be stopped. and the lever 19 shifted into itsmidway position II- If, on the contrary, the blades are not selflockmgthe lever 19 after the reversal has: taken place, is left in positionIII (for astern.

movement) and the pump is kept working.

For going ahead again the operatin lever 1sput mto position I and aftercompletion of the reversal elther stopped or kept working,

se m

according to whether the blades are self-locking or not. When operatingin the manner just described, the reversal in each sense is performedagainst the full force of the reacting water and under the consequentamming act ion and friction in the pivots of the blades. In order toavoid such friction during the act of reversal this latter maypreferably be initiated by reducing for a short time the speed ofrevolution of the propeller and motor, whereby the blades are relievedfrom their propelling thrust and from consequent friction in the pivots.The fluid pressure re quired to turn the blades will be considerablyreduced. After reversal the propeller may assume its normal speed again.

Fi s. 5 and 6 represent a modified form of the b lades and their pivots,providing a more convenient shape of their roots and improved means forrelieving the various pivot surfaces from undue pressure during reversalwithout having recourse to a temporary reduction of the speed of thepropeller. annular contact surface between the shoulder 35 of the pivotand the bi-partite nut 33 contains an annular relieving groove 34 towhich the fluid pressure has access in order to balance both the fluidpressure against the inward face of the pivot and the centrifugal forceof the blade. At suitable points of the The cylindrical surfaces of the'pivot and its seat relieving grooves 36 and'37 are also rovided, towhich fluid pressure is admitte so as to counteract the jamming actionof the propeller-thrust during reversal.

The relief of the thrust bearing of turbine ting pressure fluid from theannular shaftconduit (then in communication with the pump and under highpressure) into the annular space 30 (Fig. 1) of the thrust-bearing:

Havlng now described my invention what I claim and desire to secure byLetters Patent of the United States is 1. In a propeller, thecombination with a hub and blades adjustablymounted thereon, said huband blades havin inter-communieating internal recesses, of xed platesdividing the recesses in the blades intocompartments, a longitudinallyhollowed shaft having lateral passages communicating respectively withthe aforesaid compartments, a tube within said shaft communicating withone of said passages, a pump for supplying pressure fluid, and three-waycocks or seectively directing said fluid as desired to one or other ofsaid passages.

2. In a propeller, the combination of a pluralityof adjustable bladeseach having at its FIG root an internal cavity divided into twocompartments, a hub carrying said blades and aving passages communicatinwith all the said compartments, a hollow s aft carrying said hub andhaving passages communicating with the passages in the hub for directinga pressure medium selectively to one of the two compartments in eachblade, and means for supplying said pressure medium.

3. In a propeller, the combination of a hub, pivotal blades carriedthereby, each having a plurality of internal com artments, two pressurefluid conduits each aving communication with one of the compartments ofthe various blades, means for sup lying pressure fluid to said conduit,contro ling means therefor having passages communicating respectivelywith said conduits, two valves re-- spectively controlling saidpassages, means for simultaneously actuating said valves so that the oneacts to admit pressure fluid to its particular conduit while the otherrelieves the other conduit.

4. In an adjustable ropeller, the combination of a hub, bladbs pivotallycarried thereby, means for'admitting ressure fluid to said blades so asto turn t em on their pivots, a flange on said blades, and a bi-partitenut under said flan e, said hub being provided with a recess w 'ch islocated between said nut and the root of the propeller and constitutesan annular chamber serving to relieve the fluid pressure.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

i WILHELM SCHMID.

Witnesses:

TOH. HEINRICH FREY, A. LIEBERKNEOHT.

